sqlitebrowser: 3.10.1 -> 3.11.2

The latest releases of `sqlitebrowser` contain several new features like
a dark mode, improved CSV import/export and a lot of new bugfixes:

https://github.com/sqlitebrowser/sqlitebrowser/releases/tag/v3.11.2
https://github.com/sqlitebrowser/sqlitebrowser/releases/tag/v3.11.1
https://github.com/sqlitebrowser/sqlitebrowser/releases/tag/v3.11.0

Also some minor changes were applied to the package definition:

* Using the `pname`/`version` convention now.
* Use internal `qscintilla` rather than our package to fix the build
  (https://github.com/sqlitebrowser/sqlitebrowser/issues/1348#issuecomment-374170936).
  This can probably be removed when https://github.com/NixOS/nixpkgs/pull/56034 is merged.
* Dropped patch which removed Test and Print support as QT 5.12 is now
  used to build the application.